Today’s main topic is going to be using commas to set off parenthetical elements. A parenthetical element is any word or group of words that can be removed from the sentence without changing the sentence’s meaning. There are a whole lot of things that fall under this category; let’s list some.

Appositives

An appositive is a noun or a noun phrase (that’s a noun and the adjectives that modify it) that sits right next to another noun in the main sentence and describes it. If you see two nouns in a row, it’s likely that it’s an appositive and requires two commas, one on each side of the phrase, to set it off.

Correct: Martin, the president of the company, decided against having a bounce house in the office.

Interjections

An interjection is an expression of emotion that you often see accompanied by an exclamation mark: Hooray! Finally! Oh no! Wow! These words and phrases can also be set off by commas, usually at the beginning of a sentence.

Correct: Oh dear, the humans are attacking our planet again.

Participial Phrases

A participial phrase consists of the present participle (-ing form of a verb) or past participle (-ed form) and any modifiers. It is found at the beginning or end of a sentence.

Correct: Frightened out of her wits, Melanie quickly hid behind an elephant.

Correct: The elephant sat down leisurely, noticing that the ground beneath it seemed rather lumpy.

Absolute Phrases

An absolute phrase is almost, almost a sentence; the only thing it is missing is a form of the verb “to be.” It includes a noun and a form of a verb, but not a verb itself (it’s kind of close to the participial phrase as well, but the noun makes all the difference.)

Correct: Eliza spun in dizzying circles on the lawn, her skirt billowing out beneath her.

Vocatives

Some of you may remember the vocative from Latin classes (Et tu, Brute?) For those of you less fortunate, a vocative is a name or other specific description of someone who is being directly addressed.

Correct: Go away, you obnoxious creature.

Correct: Leonard, do you know where my viola is?

Introductory Words

There are several key words that use a comma before introducing a new idea. These include “however,” “well,” and “yes.” When you see these in a sentence, bring out that comma!

Correct: It’s not like I enjoy always being right; however, I’m afraid you are once again mistaken in this case.

Correct: Yes, that is definitely an aardvark.

Prepositional Phrases (AT THE BEGINNING of a sentence)

Remember prepositions? Those tiny little words like “after,” “until,” “through,” and so many more? Well, if you see a phrase beginning with one of those words at the beginning of a sentence, use a comma to set it off—BUT ONLY if the phrase contains a verb form.

Correct: After we ate lunch, we explored the nearby caves.

How NOT to use a comma

Now that we’ve covered many of the proper usages of commas and parentheticals, let’s take a moment to address some of the incorrect usages of commas with phrases that might at first glance appear to be parentheticals.

NO COMMA with an infinitive phrase

An infinitive is the form of a verb that includes the word “to” in front of it: “to be,” “to think,” “to act.” Do not use a comma when you see one of these in the middle of a clause.

Incorrect: I specifically asked you, to think of seven examples of misused commas.

NO COMMA with a gerund phase

This is a tricky one because gerunds are easily confused with participles (that’s a whole different post.) Like some participles, the gerund ends in –ing; however, it is specifically used as a noun. If you see an –ing phrase in a sentence, check to see if it is a) the object of a preposition or verb or b) the subject of the sentence.

Incorrect: Playing chess with his friends, was George’s favorite way to spend his time.

NO COMMA with prepositional phrases in the middle of a sentence (unless it’s especially long)

Prepositional phrases are generally essential to the sentence. Don’t mistake them for parentheticals!

Incorrect: We sat down, after a long walk, and rested our weary bones for a while.

BUT correct: We sat down, after a long walk that exhausted us and included many adventures that would take too long to tell, and rested our weary bones for a while.

NO COMMA with prepositional phrases at the beginning of a sentence that DO NOT contain a verb form

Incorrect: After lunch, we explored the nearby caves.

That concludes part 2 of this guide to commas! Stay tuned for even more next week. One last tidbit: Remember how last week I left out a comma? Well, it seems to have reappeared in this post, but I’m afraid it’s sadly misplaced. Find the misused comma (again, I hope there’s only one!) and win more happy feelings from me.

Emily Rae Robles is something of a literary prodigy, and we’re so glad to have found her! Growing up her dream was to become a professional reader, not the more commonplace ballerina or veterinarian. Her parents often punished her by taking away her reading privileges back then. She credits CS Lewis and Chaim Potok for changing her view on literature and life. She can be reached via email or Twitter. You can also learn more about her by visiting her blog, The Paradoxymoron: www.emilyraerobles.wordpress.com

I’m sure at one time I had to know all those names but somewhere along the way those have disappeared under the brain dust. Fortunately, I think I still remember the proper usages. Thanks for a mind-boggling reminder.